Textarea Limiter problems

kennethlove · May 1st, 2007, 03:05 PM

Hey all. I followed the guide in the "Professional Javascript for Web Developers" book to create a maxlength'd textarea, and it works. You can only put in a set number of characters. The problem comes when you've reached the limit and want to delete some of your characters. Apparently Javascript is picking up the delete/backspace key presses and blocking them.

So, my question is how to unblock those keys?

oh, and for those not familiar with the example, here's what I'm using:

Code:

var TextUtil = new Object();
      TextUtil.isNotMax = function(oTextArea) {
        return oTextArea.value.length != oTextArea.getAttribute("maxlength") - 1;
      }

Which gets fired off onkeypress.

mat41 · May 1st, 2007, 06:28 PM

Here is one that works very well, i use it alot. Its cut n paste and gives an example of how to use multiple char limit text areas on a page, very useful...

<html>
<head>
  <title>Untitled</title>
   <SCRIPT LANGUAGE="JavaScript">
   function textCounter(field,cntfield,maxlimit)
   {
      if (field.value.length > maxlimit)
         field.value = field.value.substring(0, maxlimit);
      else
         cntfield.value = maxlimit - field.value.length;
   }
</script>
</head>
<body>
<form name="myForm"><textarea name="message1" wrap="physical" cols="28" rows="5" onKeyDown="textCounter(document.myForm.message1,do cument.myForm.remLen1,125)" onKeyUp="textCounter(document.myForm.message1,docu ment.myForm.remLen1,125)"></textarea>
<br>
<input readonly type="text" name="remLen1" size="3" maxlength="3" value="125">
chars left
<br>
<textarea name="message2" wrap="physical" cols="28" rows="5" onKeyDown="textCounter(document.myForm.message2,do cument.myForm.remLen2,125)" onKeyUp="textCounter(document.myForm.message2,docu ment.myForm.remLen2,125)"></textarea>
<br>
<input readonly type="text" name="remLen2" size="3" maxlength="3" value="125">
chars left
<br>
</form>
</body>
</html>

Wind is your friend
Matt

joefawcett · May 2nd, 2007, 01:20 AM

I think you need to test the keyCode, if it's 8 (backspace) then skip the rest of the function. There maybe other keyCodes you need to test for such as delete and the arrow keys.

--

Joe (Microsoft MVP - XML)

kennethlove · May 2nd, 2007, 10:58 AM

joefawcett actually hit the same solution I did. Tested for the keypress, if it was 8 (backspace) or 46 (delete), then I let the keystroke through, otherwise, if the limit has been reached, the key is blocked. I figured it out about 2 minutes after posting, in typical self-help-desk fashion.